Physiologic neonatal jaundice
is yellowing of the skin and whites of the eyes due to elevation
of a breakdown product of old blood cells called bilirubin
that builds up in newborns due to immaturity of liver enzymes.
Pathologic neonatal jaundice can also result from various disease states. Phototherapy with special lights, or more aggressive therapy, may be needed to lower bilirubin to safe levels.